I work with local PD and use a Motorola APX7000 with a stubby antenna. And I also have a Kyrocera Brigadier. I can't tell you how many times the phone has lost all service in areas and so have others around me on other networks. Making them useless. But the radio still worked fine. OTOH, Been way to many times I key up and get the familiar "BUUUUURRRRR" sound because it can't digitally connect to the tower.... And at times, BOTH failed. This has bad idea stamped all over it. Straight digital radios are bad enough between the 2-3 second delays and random inability to either send or receive traffic although it claims full signal connection to tower.... I've done the "don't shoot" test before. All the other end got was "oot". Then, Theres times my phone can't get a signal for periods of time or doesn't work because the tower is overloaded on traffic leading to dropped/missed calls, messages not sent or received, and definitely no data. Putting everything on one "system" is begging for more problems.... Cell networks are far to saturated as it is.... Whether you have priority traffic or not. The hardware doesn't care when it decides to go down....
Just my thoughts and experiences as meaningless as they are.

It's funny, every time this thread pops up I'm in Schaumburg at an Astro 25 class. One of the things we played with last time I was here (granted this is a lab environment) was the WAVE LTE gateway. Well, acquisition times will vary between the two formats however, once permitted P25 takes roughly 50-100ms to process the audio (so a relatively small latency). LTE on the other hand, about 2100 ms.

As I've said previously, LTE is not going to be a solution everywhere due to existing coverage issues and will likely not be a practical voice solution for primary communications (the hardware requirements needed to lower the latency to match that of P25 will put the handsets in the same price range as P25 portables). Cities/metroplexes…it'll be good but it'll have issues in the more rural areas.

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If a repeater IDs and no one is on frequency to hear it, does it even make a sound? Yes, because KC5MVZ is monitoring you…